1. Field of the Invention
The present Invention relates generally to machines for building heat exchanger cores. More particularly, the present invention relates to such machines have a guide mechanism for properly aligning the tubes of the core during manufacturing.
2. Disclosure Information
Known heat exchanger cores typically include a plurality of flattened tubes with undulating fins, top and bottom end plates or endsheets extending parallel to the tubes and side header plates through which the ends of the tubes extend. Such core assemblies are used in automotive radiators, heater cores, condensers, evaporators and the like.
To manufacture such core assemblies, it has been known to provide an array of flattened tubes, interposing the fins between the tubes, simultaneously apply forces to the ends of the tubes to bring the tubes in general alignment, then compacting the tubes transversely, forcing the header plates over the ends of the tubes and deforming the ends of the tubes. The array of tubes can be formed by disposing the tubes into an alignment device which aligns the tubes in properly order and provides space between the tubes for the fins.
One type of alignment device comprises a hardened steel mechanism often referred to as a "picket" because of its resemblance to a picket fence. The picket includes a plurality of hardened steel fingers which receive tubes between the fingers. This machinery works very well, except when the tube dispensing device misfeeds the number of tubes per slot. When this happens, the fingers plastically deform and the guide member must be repaired or replaced.
Another type of alignment device is described in U.S. Pat. Nos. 4,611,375 and 5,014,422. These patents teach individual finder assemblies linked together by a chain or other device. The fingers can be moved relative to one another to provide a wide space for the tubes and fins. After the tubes and fins are in place, the chain moves the fingers together to exert a clamping force to properly locate the tubes with respect to their respective headers. These devices are expensive and very complex.
Therefore, it would be advantageous to provide a mechanism which is less costly and complex, but which can overcome the problems associated with tube misfeeding. It is an object of the present invention are to provide an improved apparatus wherein the tubes need not be delivered to that initial array in such precise fashion and wherein the tube guiding device is elastically deformable.